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roaming globeSolutions for 4G LTE Roaming

Flexible, scalable and cost effective solutions providing seamless roaming between legacy 2G/3G networks and todays 4G LTE networks.

4G LTE Roaming

roamingThe rollout of 4G LTE networks continues unabated. Worldwide, mobile networks are made up of a morass of 2G, 3G and 4G technologies. How do operators seamlessly navigate these networks in order to successfully provide roaming services for their subscribers, and how do they easily and cost effectively take advantage of lucrative roaming revenues from inbound roamers?

The Problem

problemTechnically the problem is simply that you have to bridge 2G/3G networks built on legacy SS7 technology with leading edge 4G LTE networks built on Diameter. What is required is a bridge between these technologies, one that will seamlessly allow the sharing of policy, charging and authentication information.


The Solution

The product that supplies this functionality is a Diameter Signalling Controller (DSC) or more accurately the Interworking Function (IWF) which is a sub component of the DSC.

Interworking Function in Diameter Signalling Controller


Interworking Function

iwf cog iconThe process of policy, charging and authentication for roaming is carried out in SS7 networks by the Mobile Application Part and/or CAMEL (CAP - Camel Application Part). These protocols communicate between the MSC/GMSC and HLR/VLR and billing modules. On the Diameter side the Attribute-Value Pairs (AVPs) are used to communicate with the equivalent functions in the LTE network namely between the DRA and HSS, OCS. This interoperability is specified as follows: Diameter to SS7 MAP interworking 3GPP TS 29.305 Diameter to SS7 CAMEL 3GPP 32.29

As with all specifications vendors implement according to their interpretation of the specs. If there are differences of interpretation with legacy equipment there may simply be no way of requesting changes to end of life equipment. Alternatively your Diameter vendor may only be willing to release changes as part of major upgrades sometime in the future.


DSC manipulationTo mitigate against this as with all SVI products the DSC comes with a powerful, regular-expression based manipulation engine allowing all parts of a protocol message to be created, modified, replaced or removed, ensuring full interoperability between vendors/devices and comprehensive message normalisation. Messages can be captured from the live network and loaded offline into the manipulation engine to test modifications and changes before going live.


toolkit boxThe SVI-DSC goes one step further with support for the Service Creation Toolkit. As part of the roaming process, and especially on the legacy networks, there may be lookups or enquiries to billing, number portability, routing or OSS platforms over perhaps SOAP, RADIUS, SQL or LDAP. Messages triggered at the SVI-DSC are sent to the Python based toolkit where message decode, manipulation and logic can be applied to deliver the required message sequence. Sequencing can be designed and tested offline enabling smooth and rapid rollout onto the live environment.

Benefits of the SVI-DSC


scalableFor those operators in the early stages of 4G LTE rollout the number of 4G subscribers will be relatively low; Furthermore the percentage of 4G subscribers that roam will be even lower. Our SVI-DSC provides clients with the opportunity to start by supporting relatively low quantities of roaming transactions and scale up, allowing for growth when demand increases through a flexible licensing option.

Cost Effective

cost effectiveMany networks that opt for a single vendor can find themselves squeezed on single function, edge of network components especially when a service is starting small.

Here at Squire Technologies we understand this and deliver the SVI-DSC on flexible licensing options to match your scaling requirements and hence deliver a cost effective solution with a clear upgrade path.


Services & Expertise

handshakeThe Squire Technologies team have been providing signalling interconnect solutions to the Telecoms industry for over 15 years. Whatever signalling interworking challenges you may be encountering give our Squire Tech team of signalling experts a call today to find out how we can help solve the problems within your network.